An introduction, preface or preamble.

plural of proem

(botany) A cluster of cells in the ovule of a fertilized flowering plant that has not yet formed into an embryo / (botany) The protonema of mosses

Of or pertaining to a proem or proemium.

The addition of a day to the lunar calendar.

plural of proemium / plural of proemion

A preface or introduction; a proem.

plural of proembryo

That produces embryogenesis

(botany) Relating to a proembryo